The present disclosure relates to image forming apparatuses.
For the purpose of economical use of resources, an image forming apparatus may perform generally-called backside printing. Backside printing is printing through reuse of a sheet (recording medium) bearing an image on only one side thereof, to form an image that a user requests on the other side of the sheet. Of a sheet used for backside printing, the side of the sheet on which an image has been already formed is hereinafter referred to as a first side and the other side opposite to the first side is referred to as a second side.
In a situation in which an image containing confidential information such as a personal name, business connection name, telephone number, knowhow information, etc. (a confidential information image) is formed on the first side of a sheet that is to be used in backside printing, there is a demand for masking of the confidential information image in order to prevent leakage of the confidential information. A certain image forming apparatus (device for processing a sheet subjected to imaging) masks a confidential information image through masking processing.
The image forming apparatus scans an image formed on the first side of a sheet in the masking processing. The image forming apparatus then masks the confidential information image based on the scanned image. In a situation, for example, in which the scanned image includes a hatched portion, the image forming apparatus forms and layers an image including a black sloid pattern portion located in correspondence with the hatched portion on the image formed on the first side of a sheet. In a situation in which the scanned image includes a specific sign, the image forming apparatus forms and layers an image of a black solid pattern corresponding to the entire region of the scanned image on the image formed on the first side of the sheet.